How does a batch file work?

Now, consider the following instructions
md \newdir
copy \dos\*.exe \newdir
cd \newdir
cd \
Executing commands at DOS prompt:
Normally, we can execute only one MS-DOS command at one time (except we use a “trick”). We cannot give another instruction before DOS has done our current command.
If we manually instruct DOS to execute the above commands, we have to type each command at theDOS prompt one after another.
Executing commands in a batch file:
However, if we put all of the commands in a text file in the same manner as in the above box, it becomes an executable program.
Let’s name it anyname.bat Similar to a COM or EXE command, we can simply type the name of this batch file at the DOS prompt to start our instructions.
i.e. C:\>anyname or C:\>anyname.bat (note: the extension bat is optional here. It makes no difference, no matter we put it or not.)
DOS will then execute the commands automatically in the same order as written in the anyname.bat The followings are details of what DOS will do for us:-
1. Creates a new directory under the root called newdir
2. Copies all files under the DOS directory with an extension of EXE to the newly created newdir directory.
3. Changes the current directory to newdir directory
4. Display the directory listing of newdir directory
5. Changes the current directory to root directory